Sewer cleaning brush and method of fabricating the same



April 18, 1967 c, J, PRANGE 3,314,095

SEWER CLEANING BRUSH AND METHOD OF FABRICATING THE SAME Filed Sept. 24, 1965 in? I I. 1 (N Z414 M V W INVENTOR [mews zlPm/vse Arron/5y United States Patent 3,314,095 SEWER CLEANING BRUSH AND METHOD OF FABRICATING THE SAME Charles J. Prange, Lima, Ohio, assignor to Flexible Sewertool Corporation, Lima, Ohio, a corporation of Ghio Filed Sept. 24, 1965, Ser. No. 489,843 Claims. (Cl. 15-1042) This invention relates to brushes for cleaning sewer conduits. Its general object is to provide an extremely sturdy, rugged and long-wearing brush which is yet of relatively inexpensive construction. Toward the attainment of this general object the invention provides a brush:

(1) Of all-metal construction comprising a holder of simple tubular construction and a plurality of securing stems of flexible rod-like metal extending through the holder, anchored therein and projecting radially therefrom to provide a plurality of scouring fingers.

(2) Wherein the scouring fingers are of extremely tough, highly flexible material, for which braided wire cable material can be utilized.

(3) Wherein the holder comprises two parts which are operable to clamp the scouring stems between them in a manner such as to securely anchor them against radial displacement.

(4) Wherein the holder comprises an elongated core member surrounded by a sleeve member and wherein the scouring stems are securely anchored therein by relative axial displacement of the core and sleeve members and securing them in such displaced condition to produce axial clamping of the scouring stems between them.

(5) Whereinthe sleeve is of sufficiently larger diameter than the core to provide an annular radial gap between the two holder parts, in which traversing portions of the scouring stems are deformed axially to provide offset portions which function to securely lock the scouring stems to the holder against radial displacement.

While the invention can be applied to a rotary brush, it is directed primarily to a drag brush for finishing operations in a sewer conduit that has been largely cleaned out in a preliminary cleaning operation in which sediment and a majority of intruding tree roots and other foreign material are removed by drag-bucket or rotary cleaning (e.g. cutting) tool operation. Such a finishing operation may be desired in order to remove the remnants of intruding tree roots dangling from the top of a sewer conduit, or for removing encrusted scale deposits which are not readily removed by drag-bucket or rotary cutter operation. A further object of the invention is to provide a brush of a rugged construction which can be provided in relatively large sizes for cleaning sewer lines anywhere from 6 inches to 36 inches in diameter or even larger.

Other objects and advantages will become apparent in the ensuing specification and appended drawing in which: FIG. 1 is a side elevational view of a sewer-cleaning brush embodying the invention;

FIG. 2 is an end view of the same;

FIG. 3 .is a fragmentary longitudinal sectional view of the initial assembly of holder and scouring stem parts before axial displacement of the holder parts and offsetting deformation of the scouring stems;

FIG. 4 is a fragmentary axial sectional view of the assembled brush showing the fastener bolt which secures the holder parts in their axially offset relation;

FIG. 5 is a schematic view illustrating the method step of axial displacement of the holder parts during fabrication of the brush; and

FIG. 6 is a fragmentary view of a modified form of the brush embodying bristle-like scouring fingers of frayed-cable construction.

Referring now to the drawing in detail, I have shown 3,314,095 Patented Apr. 18, 1967 therein, as an example of one form in which the invention may be embodied, a brush comprising, in general, a holder A; a plurality of scouring stems B extending through the holder and projecting approximately radially therefrom to define a plurality of scouring fingers; and a pair of bails C secured to respective ends of the holder for attachment of the brush to a pair of drag lines such as are commonly employed for pulling drag buckets and similar cleaning tools through a sewer conduit. The invention contemplates providing the brush in a series of sizes ranging upwardly from a minimum diameter which may be as much as six inches, upwardly through a range of diameters which may extend as high as 36 inches or more. The external diameter of the brush, at the tips of the scouring fingers, is just suificiently smaller than the internal diameter of the sewer conduit to be cleaned so as to avoid having the brush become stuck in the conduit when used in a finishing operation for which it is designed. Since the principal function of the brush is to remove crusted scale, tree root fragments and the like which remain within the sewer conduit after the major accumulations of sediment and other obstructions have been cleaned out by operation of a drag bucket or rotary cutting tool or other cleaning implement therein, the diameter of the brush will be such as to almost fill the cross section of the conduit.

The holder A comprises a tubular core 10 and a surrounding sleeve 11 of sufficiently larger diameter to provide an annular radial gap 12 of substantial width separating these two holder parts. The bails C are secured as by welding at 13 to the respective ends of core 10.

Core 10 is provided with pairs of transversely opposed bores 14 and sleeve 11 is provided with correspondingly positioned pairs of apertures '15, for reception of the scouring stems B. Like the bores 14, the apertures 15 are preferably in the form of cylindrical bores. The core 10 is preferably of cylindrical tubular form although it can be of hexagonal or octagonal or other regular polygonal tubular form, or can be of solid cylindrical or prismatic form. Likewise the sleeve 11 is preferably of cylindrical form but can be of a regular polygonal cross section, tubular form.

The scouring stems B are of an extremely tough, hard, stiff but slightly flexible long-wearing material for which braided steel wire cable is preferred. Each of the scouring stems B comprises a central portion 21 extending transversely through the core It), a pair of spaced intermediate portions 22 which, in the assembled brush, are deformed into the axially offset form shown at 23, and respective free end portions 24 which project generally radially from the sleeve 11 to constitute a plurality of scouring fingers. In most instances, the ends of the Wire strands of which the fingers 24 are composed are welded to one another to provide integral, non-fraying tips 25 which maintain the cylindrical rod form of the fingers. In some instances, however, it may be preferable to leave the ends of the cable strands free so that the strands may fray outwardly into brush-bristle form, as shown in FIG. 6.

The deformation of the intermediate portions of the scouring stems into the axial offsets 23' is accomplished by relative axial displacement between the core 10 and the sleeve 11. These two holder parts are held in the axially displaced relation by a fastener pin 26 (preferably a bolt as shown) or the like extending through pairs of diametrically opposed fastener holes 27 and 28 in the holder parts 10, 11. The holder parts 1.0, 11, when thus secured in axially displaced relation, will exert clamping pressure against the extremities of the offsets 23 such that the latter will provide exceedingly secure anchorage of the scouring stem against radial displacement in the holder A.

Referring now to FIG. 5, the bores 14 and apertures 15 are arranged in regular circumferentially spaced and axially spaced relation which may be such that one or more series of consecutive bores (or apertures) extends helically around the holder A as indicated in FIG. 1. This makes it possible to extend the scouring stems B diametrically through the holder A without interference between the central portions 21 thereof, there being an axially progressive array of stems which are in crossed but non-contacting relation within the core 10, as best shown in FIG. 3.

Method of fabricating In the preparation of holder parts ltl, 11, the bores and apertures 15 are arranged in matching positions such that, in an initial assembly position of these parts, each pair of bores 14 can be registered on a common diametral axis with a corresponding pair of apertures 15. This matching arrangement can, if desired, be readily obtained by securing the core and sleeve in coaxial relation in a suitable drilling fixture and then proceeding to drill each set of paired bores and paired apertures by drilling all four of them in a single drilling operation extending diametrically through both sides of the sleeve and of the core. Alternatively, it can be accomplished by positioning the holder parts 10, 11 in a rotatable drill jig having diametrically opposed drill guides and drilling independently from both sides, With one pair of matched bores 14 and 15 being simultaneously drilled. After the groups of bores 14 and apertures 15 have been completed, with all sets in registering relation, the holder parts, 10, 11 are shifted axially to the extent of the axial displacement in the final assembly, and are held in such displaced relation while the fastener bores 27 and 28'are drilled through the sleeve 11 and core 19. Again, this can be accomplished by a single drilling operation extending entirely through the assembled sleeve and core from one side to the other or by drilling separately from each side with a bore 27 and a bore 28 being drilled in the same drilling operation, but without permitting any axial shift of the parts 10, 11 between the two drillings.

When the scouring stems are to be assembled in the holder, the core and sleeve 11 are positioned, as in FIG. 3, with each pair of apertures on a common diametral axis with its respective pair of bores 14 in fully registering relation. The bores 14 and apertures 15 are sufficiently larger in diameter than the scouring stems B so that the latter can be readily passed through the registering apertures and bores. This step is performed in any suitable manner, as by positioning the holder parts 10, 11 with their common longitudinal axis extending vertically and shifting the stems B horizontally into the holder, through the registering bores and apertures. After all of the stems have been assembled in the holder, the ends of the scouring fingers 24 are adjusted to positions in which their extent of radial projection is uniform so as to provide a cylindrical periphery for the brush. The assembly is then placed between vertically opposed pressure applying members such as the bed 30 and ram 31 of an arbor press, and pressure is thereby applied to one end of the core 10 and the opposite end of the sleeve 11 until the parts 10, 11 are axially displaced to bring the fastener holes 27, 28 into registration on a common diametral axis. The fastener bolt 26 is inserted through the sleeve 11 and core 10 while these parts are held in these relative positions, and the bolt 26 is then secured by a suitable nut 33. The bails C may be attached to the ends of the core 10 either before or after the assembly operation described above.

In the operation of my improved drag brush, it is pulled through a sewer conduit that has been previously cleaned out by drag bucket or rotary cutting tool operation, the tips of scouring fingers 24 exerting a scouring action against the inner wall of the conduit so as to sever therefrom, accumulations of scale, protruding tree roots, and

other clinging foreign material which has not been removed by the preliminary stage of cleaning operation.

As seen in FIG. 1, the scouring fingers 24 project from sleeve 11 at a slight inclination from truly radial positions. This is an incident to the axially offset deformation of the intermediate portions of the scouring stems. It is not objectionable, nor is it an essential feature of construction for proper operation of the brush.

I claim:

1. A brush for cleaning sewer conduits, comprising, in combination: a tubular core having therein a plurality of pairs of transversely-opposed bores; a sleeve surrounding said core and separated therefrom radially by an annular gap, said sleeve having a plurality of pairs of apertures in positions matching those of said bores and approximately radially opposed thereto but displaced axially therefrom; a plurality of stiff, flexible scouring stems each extending through an opposed pair of said bores, having axially offset portions traversing said gap at opposite sides of the brush and having free end portions projecting generally radially outwardly from said sleeve to constitute scouring fingers; and fastener means securing said sleeve to said core in axially-displaced relation thereto such as to clamp said stems between said sleeve and core and to lock said axially offset portions of the stems into said gap, thereby securely anchoring said stems against radial displacement in said core and sleeve, said core and sleeve having respective fastener holes in alignment on a common diametral axis when said bores and apertures are relatively displaced axially as aforesaid, and said fastener means comprising a pin extending diametrically through said holes and means securing it against displacement from said holes.

2. A brush for cleaning sewer conduits, comprising, in combination: a metallic tubular core having therein a plurality of pairs of diametrically-opposed bores; a sleeve surrounding said core and separated therefrom radially by an annular gap, said sleeve having a plurality of pairs of diametrically-opposed apertures in positions matching those of said bores and approximately radially opposed thereto but displaced axially therefrom; a plurality of lengths of braided steel wire cable each having a central portion extending diametrially through said core and each extending through opposed pairs of said bores and apertures, having deformed portions traversing said gap at opposite sides of the brush and having free end portions projecting generally radially outwardly from said sleeve to constitute scouring fingers; said deformed portions being offset in said gap with reference to said central portion in a direction parallel to the axis of said core and sleeve, and fastener means securing said sleeve to said core in axially-displaced relation thereto such as to clamp said lengths of cable between said sleeve and core and to lock said deformed portions thereof into said gap so as to securely anchor said scouring fingers against radial displacement in said core and sleeve.

3. A brush as defined in claim 2, wherein said fingers have integral tips constituted by welded-together ends of the cable strands.

4. A brush as defined in claim 2, wherein said fingers are composed of cable strands frayed outwardly into bristle form.

5. A brush as defined in claim 2, wherein said gap has a radial Width sufficient to receive said deformed portions in said offset conditions.

References Cited by the Examiner UNITED STATES PATENTS 1,663,l94 3/1928 Denman 15200 2,072,110 3/1937 Jennings 15-198 2,626,413 1/1953 Girton 1550 2.

CHARLES A. WILLMUTH, Primary Examiner.

E. L. ROBERTS, Assistant Examiner. 

1. A BRUSH FOR CLEANING SEWER CONDUITS, COMPRISING, IN COMBINATION: A TUBULAR CORE HAVING THEREIN A PLURALITY OF PAIRS OF TRANSVERSELY-OPPOSED BORES; A SLEEVE SURROUNDING SAID CORE AND SEPARATED THEREFROM RADIALLY BY AN ANNULAR GAP, SAID SLEEVE HAVING A PLURALITY OF PAIRS OF APERTURES IN POSITIONS MATCHING THOSE OF SAID BORES AND APPROXIMATELY RADIALLY OPPOSED THERETO BUT DISPLACED AXIALLY THEREFROM; A PLURALITY OF STIFF, FLEXIBLE SCOURING STEMS EACH EXTENDING THROUGH AN OPPOSED PAIR OF SAID BORES, HAVING AXIALLY OFFSET PORTIONS TRAVERSING SAID GAP AT OPPOSITE SIDES OF THE BRUSH AND HAVING FREE END PORTIONS PROJECTING GENERALLY RADIALLY OUTWARDLY FROM SAID SLEEVE TO CONSTITUTE SCOURING FINGERS; AND FASTENER MEANS SECURING SAID SLEEVE TO SAID CORE IN AXIALLY-DISPLACED RELATION THERETO SUCH AS TO CLAMP SAID STEMS BETWEEN SAID SLEEVE AND CORE AND TO LOCK SAID AXIALLY OFFSET PORTIONS OF THE STEMS INTO SAID GAP, THEREBY SECURELY ANCHORING SAID STEMS AGAINST A RADIAL DISPLACEMENT IN SAID CORE AND SLEEVE, SAID CORE AND SLEEVE HAVING RESPECTIVE FASTENER HOLES IN ALIGNMENT ON A COMMON DIAMETRAL AXIS WHEN SAID BORES AND APERTURES ARE RELATIVELY DISPLACED AXIALLY AS AFORESAID, AND SAID FASTENER MEANS COMPRISING A PIN EXTENDING DIAMETRICALLY THROUGH SAID HOLES AND MEANS SECURING IT AGAINST DISPLACEMENT FROM SAID HOLES. 